Motor



p 1932- w. c. SPECK ET AL:

MOTOR Original Filed Jan. 14. 1929 INVENTORS ATTORNEYS Patented Sept. 13, 1932 WILLIAM G. SPECK AND EUGENE BARKER,

F COLUMBUS, OHIO, ASSIGNORS TO THE BUCKEYE STEEL GASTINGS COMPANY, OF COLUMBUS, OHIO,'A CO RPORATIO 1\I OLE OHIO Original application filed January 14; 1929 Serial No.

1931. Serial No. 521,213.

This invention relates to motors of the type which employs a piston which reclprocates in a cylinder and is operated by fillld pressure, this application being a CllVlSlOIl of our pending application Serial No- 332,344, filed January 14th, 192$),issued asv Patent No. 1, 07,181, May 26,1931. The object of this invention is to provld simple and effective means for controlllng the 6 motor and for automatically cutt ng ofi the fluid pressure supply at the end of each reciprocatory stroke of the piston to prevent building up of the air pressure.

A further object is to 'provlde improved means for regulating the extent of the strokes of the piston. W 7

Other objects will appear from the accompanying description and claims.

In the accompanying drawing:

Fig. 1 is a view partly in side elevation and partly in section of a motor embodying the improvements.

Fig. 2 isa partial enlarged end elevation looking from the left of Fig. 1.- I

Fig. 3 is an enlar ed section on the line 3-3 of Fig. 2, with 516 parts in the position when the piston is atthe limit of its stroke as shown in Fig. 1. g

Fig. 4 is an enlarged partial so looking from the right of Fig.

Fig. 5 is an'enlarged section on the line 5-5 of Fig. 4..

The motor is one particularly adapted for operating the reciprocating devices of a carrier for large castings employed in connection with the slogging and gate breaking mechanisms described in our pending application referred to, although it may be used for other purposes with equally good results. In the operation of conveying castings to the slogging and gate breaking mechanism it is desirable that the castings be moved predetermined distancesin order to position them "properly with relation to the mechanisms and that the movement of the reciprocating deend elevation cured to the forward head 2 j Moron:

332,344. Divided and this application filed March?) vices of the carrier be controlled from a cen tral station and be automatically stopped when the castings have been correctly positioned and to that end provisionismade b which the motortmay be readily controlled by the operator. to start the same and the movement of the piston be automatically stopped at thepend of a stroke in either direction, the movement of'the piston acting to operate the reciprocating devices of the carrier first in one direction to position, the castings and then in the opposite direction to restore the reciprocating devices of the carrier to the initial position.

.Thecylinder is shown at 1, its forward head be'ingindicated by 2 and its rear head by 3. 1 A piston 4 ismounted in the cylinder and has a rod 5 which forward head which has connected with its outer end a yoke-shaped member 6which in turn is connected with the parts to be reciprocated, which in the present case are the pawl-bars and keeper bars of the casting carrier which are not shown in the present case but which arefullydes'cribed inthe pending application referred to.

Provision is made for automatically relievingthe pressure of the fluid in the cylinder at'the end of each stroke thereof.- Seis a spring casing 7 which has fastenedto it a valve chamber 8. .A supply pipe 9 leads froma suitable source of controlled air pressure and exhaust to the valve chamber 8 and a second pipe 10 leads from the chamber tothe rear I end of the cylinder. The chamber 8 has a poppet valve 11' which is normally held to its seat byga spring 12 which surrounds the valve projects through the stem 13 on the" outside of the chamber and is interposed between the wall of the chamber and a collar 14 on the stem. Located in the spring casing in plunger 15 which has a reduced portion 16 surrounded by a coil spring 17 WlliChiS interposed between the end wall of the casing and the shoulder formed by the reduced portion, this spring 17 being of greater strength than the one 12. This plunger 15 has a reduced stem 18 which projects through the cylinder head 2 into the cylinder so as to normally stand in the path of the piston. Pivoted in a slot formed in the wall of the spring casing is a lever, one arm 19 of which carries an adjustable pin 20 which cooperates with the end of the valve stem 13 and the other arm 21 of which has a cam roller 22 which cooperates with the cam face 23 on the plunger 15. With the piston in the position shown in Fig. 1, the plunger 15 is pressed rearwardly by the spring 17 to bring the cam roller 22 on the high part of the cam surface so as to maintain the valve 11 in open position as shown in Fig. 5. By admitting air from a suitable controlling station (not shown) to thepipe 9 therefore the piston is moved forwardly in the cylinder 1 and so soon as it contacts with the stem 18 the plunger 15 is moved forwardly, the cam roller 22 rides to the low part of the cam and the valve 11 is closed by the spring 12 so as to shut off the air supply and stop the movement of the piston in a forward direction. 1

Connected with the rear end 3 of the cylinder is a-spring casing 24 having therein a hollow plunger 25 formed with a reduced portion 26 which is surrounded by a coil spring 27 interposed between the rear end of the spring casing and the shoulder formed by the reduced portion. 1 The forwardend of this plunger projects through theforward end of the springcasing and also through the end 3 of the cylinder andis reduced so as to form shoulders 28 and 29 to provide stops. The plunger is internally threaded to receive a threaded portion of a stop pin 30. The forward end of this pin projects into the cylinder while the rear end projects through the end wall of the spring casing and has a hand. wheel 31' by which its position in the plunger may be adjusted. Supported by the spring casing 24 is a valve chamber 32 to which leads. a pipe 33 from any suitable source of control compressed air and exhaust, and from which leads a pipe 34 tothe forward end of the cylinder. A poppet valve 35 is arranged between the inlet and outlet openings of the valve chamber and is normally held closed by a spring '36which surrounds the stem 37 of the valve on the outside ofthe chamber, the spring being interposed between the end wall of the chamber and a collar 38 on the stem.

A lever is pivoted in aslot on the under side of the spring casing, one arm 39 of which has an adjustable pin 40 which cooperates with the end of the valve stem, and the'other arm '41 of which has the cam roller 42 which cooperates with a cam surface 43 on the lunger. The, spring 27 is I of greater strength than the spring 36 so that when the pin 30 is free from the piston the plunger will be pushed forwardly by the spring 27 to cause its cam surface to operate the cam lever to open the valve. When the piston contacts with the pin 30 upon its rearward stroke however the plunger is pushed rearwardly so as to permit the cam roller to ride upon the low part of the cam and the spring 36 to close the valve. The point at which this action takes place is determined by the position of the adjustable pin 30 so that provision is therefore made for regulating the stroke of the piston.

An advantage in this arrangement is that it effects economy in the air supply to the cylinder in that it prevents air pressure from building up in the cylinder after the piston has reached the limit-of its stroke in either direction, this being particularly true upon the forward or unloaded stroke of the piston which requires a comparatively small air pressure compared to the maximum air pressure.

From this. description it will be seen that the valves 11 and 35 are normally held open by their springs and that when fluid is being admitted by one valve it is exhausting by the other valve; also that when the piston reaches the point near the limit of itsstroke in either direction it closes that valve which is admitting the fluid. The fluid is controlled at a central station (not shown) the operator admitting, fluid under pressure to either one of the pipes 9 or 33 and opening the other pipe to atmosphere.

Having thus described our invention, we claim: p v a 1. In a motor, a fluid-pressure cylinder having a reciprocating piston, a valve, said valve acting alternately to permit the supply and exhaust of fluid to and from one end of said cylinder, a spring normally holding said valve closed, a plunger controlled by said cylinder and projecting into'the path of the piston, a spring forcmoving said plunger in opposition to the movement of the piston, said plunger spring beingof greater strength than said valve spring, a cam leverhaving an operative connection with said valve, and a cam surfaceon said plunger cooperating with said lever to open 'sai'd valve when said plunger is free from the piston and-permitting saidvalve to. close when said plunger is operated by the piston.

2.- In a motor, a fluid pressure cylinder, a piston therein, a valve chamber located at one end of said cylinder, a'fluid supply and exhaust passage connecting each chamber with the opposite end of the cylinder, means for supplying and exhausting'fluid to and from each-chamber, a valve in each chamber between the fluid passage leading to the cylinder and said supply and exhaust means, a spring-pressed plunger in'each end ofthe cylinderwith one end thereof standing in the path of the piston, a cam lever for each plunger, a cam on each plunger normally causing said cam lever to hold the valve at that end of the cylinder open, said plunger when moved by contact with the piston acting to cause said cam lever to release said valve, and a spring for closing the valve when so released.

In testimony whereof, we have hereunto set our hands this 2d day of March, 1931.

WILLIAM C. SPEGK. EUGENE BARKER. 

